As for strategies and such, I guess I would be using the Soul Grinder to kill tanks and the like, the Daemon Prince and Lord of Change for tough enemy elites and HQs, the Flamers for the same sort of thing as the DP and LoC but also for taking out some troops, and the rest kind of explains itself, methinks... I'll be facing primarily Space Marines, Tau, Necrons, and Imperial Guard.

Thanks for the help.

This is my first army list, so please be as harsh as possible, as I have almost no idea what I'm talking about.

First of all, in my experience, it is best to only have one god in your chaos army.

And in my experience, multi-god is the best :)

But anyway, being a bit more constructive with my criticism:

With the armies you say you'l be facing, I don't think giving your Bloodletters an upgrade of "Fury of Khorne" is such a good idea. After all, with 5th being very close to us (or maybe you're already playing with 5th's rules), giving a model with a power weapon rending doesn't do much. A 6 on the dice will score a hit and pass through armor regardless, and it'll only really come into action against T8 models (which doesn't happen that often) or when charging tanks (but will yo really be sending your squad of bloodletters against tanks?). And even then, it's only one model that has it, so a max of 3 attacks if you get the charge, that you'll miss about half the time anyway becaues of their WS, so.... yeah, I would consider dropping it and save some points :)

Same with Instruments of Chaos. Technically, Bloodletters will pretty much always win their close combats, having a good statline, good special rule and all are equipped with power weapons. I know it's not much of a point sink anyway, but just clearing these two can save you enough points for something nice elsewhere :)

I'm not too fond of giving every troop units a Chaos Icon, if only because they're so damn expensive! But I guess it highly depends on which units you choose to deepstrike in your first turn, but still... Maybe keep one on the Plaguebearers (T5 and FNP), and one on the Horrors (good invulnerable saves), and one or both should survive to bring in the others safely. If neither your Horrors nor your Plaguebearers survived that first turn's of shooting, you might be in a good deal of trouble in your game already anyway! :D

So yeah, technically you've saved close to 80 points now... Drop Bolt of Tzeentch from the Flamers and that's another 30 points to save right there ;)

I guess with these points, buying another 3 Flamers might be a good idea! Or take Fateweaver instead of a regular Lord of Change... Lots of possibilities to fill up your list, at that point, anyway :)

All in all, though, I like your list :) Not sure I would send the Soul Grinder after tanks that much, I hear he's better protected being locked in close combat (and he's good at it too!). You can always send your Lord of Change bust up a tank by himself... with his wings and being an MC, he should do fine and won't stay locked in combat so he'll be able to still fire on stuff before and after. Just don't forget that if you want to assault a tank, to shoot at it at least once with one of his attacks (the rest can go into nearby infantry)

HQ: Drop the upgrades as you won't need more Breath of chaos if you get 3 more flamers.

Elites: Drop Bolt as they should be going for heavy infantry or hordes.

Troops: Drop 2 icons, Fury and Nox touch. Spend some points on 2-3 more plague bearers to protect the icon.

Heavy: Dont give the prince might when nox touch is better and cheaper. 2D6+5 should still be plenty against the rear armour of tanks. Give him Gaze to take advantage of BS5.
I dont like the soul grinder. One tank alone won't last long. Suggest replacing with a prince with MoT and Bolt. It is more survivable and the better BS compensates for the lower strength weapon.

These savings could get you 100 or so points for 3 more flamers or how about 2 HoT with no upgrades. They would make your Horror unit into a marine shooting wonder. 1HoT with bolt, master & legion would be simmilar but have the anti tank option too. 7 bases of nurglings could also be fun. It is important to keep your model count up especially as only half your army begins the game. The danger is that a few tooled up models deepstrike and get heavily shot to bits before being able to use those upgrades.